JP7406300B2 - Method for producing iodine-containing silicon compound - Google Patents

Description

The present invention relates to a method for producing an iodine-containing silicon compound.

Iodine-containing compounds with high EUV light absorption efficiency are expected to improve the performance of EUV resists, which is currently one of the challenges in industrializing EUV lithography. Among iodine-containing compounds, EUV resist patterning is recommended for silicon-containing resist underlayer films (hereinafter referred to as polysiloxane underlayer films) into which organic groups in which iodine is directly bonded to aromatic rings, especially phenyl iodide groups, are introduced. The possibility of performance improvement is expected.

In order to obtain such a polysiloxane underlayer film having phenyl iodide groups, a hydrolyzable silicon compound (hereinafter referred to as an iodine-containing silicon compound) into which phenyl iodide groups have been introduced is required. Methods for producing such iodine-containing silicon compounds include a method in which a Grignard reagent is prepared from a phenylbromide silane compound and Mg and reacted with iodine (Patent Document 1: paragraph [0058]), and a method in which phenylene iodide is reacted with a specific Grignard reagent. A method of reacting with tetraalkoxysilane after the reaction (Patent Document 2: paragraph [0085]) is known.

However, in the method of Patent Document 1, in order to prevent self-reactivity with the Grignard reagent, a specific group with low reactivity is required as the hydrolyzable alkoxy group of the iodine-containing silicon compound. Therefore, the hydrolysis performance of the obtained iodine-containing silicon compound is limited, and only compounds with low versatility may be produced. Furthermore, in the method of Patent Document 2, the reaction is allowed to proceed for a long time of 44 hours under mild conditions in order to prevent self-reaction, which is uneconomical.

Furthermore, as another organic chemical method, synthesis of phenyl iodide group via benzenediazonium salt as shown in the reaction formula below can be considered, but since it is necessary to use an aqueous reagent during the reaction, it is difficult to synthesize hydrolyzable silicon. It is unsuitable for the production of containing compounds.

WO01/83608 publication Japanese Patent Application Publication No. 2008-214314

As described above, there is a need for a more economical method for producing iodine-containing silicon compounds that allows the substitution position to be freely selected, does not require hydrolysis of hydrolyzable alkoxy groups, and is free from restrictions on the type of alkoxy groups. .

The present invention was made to solve the above problems, and an object of the present invention is to provide a method for economically producing a silicon compound containing an iodized phenyl group without causing hydrolysis of a hydrolyzable alkoxy group. shall be.

（上記反応式中、Ｒ^０は全て同一でも異なってもよい炭素数１～６のアルキル基、Ｒ^１は単結合または２価の有機基、Ｒ^２は炭素数１～１０の有機基、Ｒ^３は炭素数１～１０の有機基、Ｒは炭素数１～６の有機基である。ｎ０は１、２または３、ｎ１は１、２または３、ｎ２は０、１または２、ｎ３は０、１または２、１≦ｎ１＋ｎ３≦３であり、Ｘは求電子活性種として働くヨウ素の対向置換基である。） In order to solve the above problems, in the present invention, as shown by the reaction formula below, a trialkylsilyl ((R ⁰ ) ₃ Si) group bonded to a phenyl group is converted to iodine using an iodine-containing electrophile (IX). Provided is a method for producing an iodized phenyl group-containing silicon compound characterized by substitution.

(In the above reaction formula, R ⁰ is an alkyl group having 1 to 6 carbon atoms, which may be the same or different, R ¹ is a single bond or a divalent organic group, R ² is an organic group having 1 to 10 carbon atoms, R ³ is an organic group having 1 to 10 carbon atoms, R is an organic group having 1 to 6 carbon atoms, n0 is 1, 2 or 3, n1 is 1, 2 or 3, n2 is 0, 1 or 2, and n3 is 0, 1 or 2, 1≦n1+n3≦3, and X is a countersubstituent of iodine that acts as an electrophilic active species.)

With the production method of the present invention, an iodized phenyl group-containing silicon compound can be produced economically without causing hydrolysis of a hydrolyzable alkoxy group.

In the production method of the present invention, R ⁰ is preferably a methyl group or an ethyl group.

With this production method, the trialkylsilyl ((R ⁰ ) ₃ Si) group is easily eliminated, so the reaction proceeds under mild conditions, and the iodine is produced without causing hydrolysis of the hydrolyzable alkoxy group. A phenyl group-containing silicon compound can be produced more economically.

Moreover, in the production method of the present invention, it is preferable that the iodine-containing electrophilic reagent is iodine monochloride.

When such an iodine-containing electrophilic reagent is used, side reactions are less likely to occur and by-products can be easily separated, so that an iodized phenyl group-containing silicon compound can be produced even more economically.

As described above, according to the method for producing a phenyl iodide group-containing silicon compound of the present invention, it is possible to economically produce a phenyl iodide group-containing silicon compound that is industrially useful, particularly when producing an underlayer film for EUV lithography. Because it can be produced in a straightforward manner, it has very high industrial utility value.

As mentioned above, there is a need to develop a more economical method for producing iodine-containing silicon compounds that allows the substitution position to be freely selected, does not involve hydrolysis of hydrolyzable alkoxy groups, and does not impose restrictions on the type of alkoxy groups. was.

Generally, a method using an organometallic reagent, typified by a Grignard reagent, is known as a method for forming a skeleton of an organic compound or a silicon compound. However, since the iodine-carbon bond is extremely reactive, preparing an organometallic reagent while retaining iodine requires special reaction conditions, as shown in Patent Documents 1 and 2. I need. Reactions that require such special conditions lack versatility and are extremely difficult to produce the desired silicon compound on an industrially profitable scale.

As a result of intensive studies on the above-mentioned issues, the present inventors have found that after introducing a trialkylsilyl group into the required position on the phenyl group in advance, the skeleton of a silicon compound is formed by various organic reactions, and finally the trialkylsilyl group is The present invention was completed by developing a method for converting silyl groups into iodine.

（上記反応式中、Ｒ^０は全て同一でも異なってもよい炭素数１～６のアルキル基、Ｒ^１は単結合または２価の有機基、Ｒ^２は炭素数１～１０の有機基、Ｒ^３は炭素数１～１０の有機基、Ｒは炭素数１～６の有機基である。ｎ０は１、２または３、ｎ１は１、２または３、ｎ２は０、１または２、ｎ３は０、１または２、１≦ｎ１＋ｎ３≦３であり、Ｘは求電子活性種として働くヨウ素の対向置換基である。） That is, the present invention is represented by the following reaction formula, and is characterized in that the trialkylsilyl ((R ⁰ ) ₃ Si) group bonded to the phenyl group is replaced with iodine by an iodine-containing electrophile (IX). This is a method for producing an iodized phenyl group-containing silicon compound.

(In the above reaction formula, R ⁰ is an alkyl group having 1 to 6 carbon atoms, which may be the same or different, R ¹ is a single bond or a divalent organic group, R ² is an organic group having 1 to 10 carbon atoms, R ³ is an organic group having 1 to 10 carbon atoms, R is an organic group having 1 to 6 carbon atoms, n0 is 1, 2 or 3, n1 is 1, 2 or 3, n2 is 0, 1 or 2, and n3 is 0, 1 or 2, 1≦n1+n3≦3, and X is a countersubstituent of iodine that acts as an electrophilic active species.)

Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited thereto.

（上記反応式中、Ｒ^０は全て同一でも異なってもよい炭素数１～６のアルキル基、Ｒ^１は単結合または２価の有機基、Ｒ^２は炭素数１～１０の有機基、Ｒ^３は炭素数１～１０の有機基、Ｒは炭素数１～６の有機基である。ｎ０は１、２または３、ｎ１は１、２または３、ｎ２は０、１または２、ｎ３は０、１または２、１≦ｎ１＋ｎ３≦３であり、Ｘは求電子活性種として働くヨウ素の対向置換基である。） In the present invention, the ipso of the trialkylsilyl group is produced by causing an electrophilic reagent containing iodine to act on the trialkylsilyl ((R ⁰ ) ₃ Si) group that has been introduced as a leaving group onto the phenyl group. By substituting the trialkylsilyl group itself with iodine, iodine can be introduced with high regioselectivity and efficiency in a short period of time under mild conditions at about room temperature.

(In the above reaction formula, R ⁰ is an alkyl group having 1 to 6 carbon atoms, which may be the same or different, R ¹ is a single bond or a divalent organic group, R ² is an organic group having 1 to 10 carbon atoms, R ³ is an organic group having 1 to 10 carbon atoms, R is an organic group having 1 to 6 carbon atoms, n0 is 1, 2 or 3, n1 is 1, 2 or 3, n2 is 0, 1 or 2, and n3 is 0, 1 or 2, 1≦n1+n3≦3, and X is a countersubstituent of iodine that acts as an electrophilic active species.)

The raw material used in the production method of the present invention, that is, the silicon compound having a trialkylsilyl ((R ⁰ ) ₃ Si) group bonded to a phenyl group, is a compound represented by the following general formula (1) (hereinafter referred to as "trialkylsilyl"). (Also referred to as "alkylsilylphenyl group-containing silicon compound.")

R ⁰ is an alkyl group having 1 to 6 carbon atoms which may be the same or different, preferably an alkyl group having 1 to 3 carbon atoms, and a methyl group or ethyl group is preferable because the elimination ability of the (R ⁰ ) ₃ Si group is increased. More preferably, it is a group.
R ¹ is a single bond or a divalent organic group, and examples of the divalent organic group include, but are not particularly limited to, linear, branched, or cyclic alkylene groups, carbonyl groups, ester groups (carbonyloxy groups), Mention may be made of ether groups, etc., as well as combinations thereof. Examples of the alkylene group include a methylene group, an ethylene group, and a propylene group. Examples of the combination include a combination of a carbonyloxy group and an alkylene group (carbonyloxymethylene group, carbonyloxypropylene group, etc.) .
R ² is an organic group having 1 to 10 carbon atoms, and examples thereof include linear, branched, or cyclic alkyl groups, alkoxy groups, and ester groups, and the alkyl groups further include ester groups, ether groups, etc. You can leave it there. Examples of R ² include a methyl group, an ethyl group, and a propyl group.
R ³ is an organic group having 1 to 10 carbon atoms, and examples thereof include the same groups as R ² above.
R is an organic group having 1 to 6 carbon atoms, and examples thereof include linear, branched, or cyclic alkyl groups. Examples of R include a methyl group, an ethyl group, a propyl group, and a butyl group.
n0 is 1, 2 or 3, n1 is 1, 2 or 3, n2 is 0, 1 or 2, and n3 is 0, 1 or 2. Since 1≦n1+n3≦3, the above raw material has 1 to 3 (OR) groups and is hydrolyzable.

In the present invention, the trialkylsilyl ((R ⁰ ) ₃ Si) group bonded to the phenyl group of the trialkylsilylphenyl group-containing silicon compound is substituted with iodine by the iodine-containing electrophile (IX). Therefore, a trialkylsilyl phenyl group-containing silicon compound having the above-mentioned trialkylsilyl group (leaving group) at the iodine substitution position of the desired iodized phenyl group-containing silicon compound may be selected as the raw material.

Next, the iodine-containing electrophilic reagent (I-X: I is iodine, and X is a counter substituent of iodine that acts as an electrophilic active species) used in the present invention includes iodine, halogenated iodine ( Examples include iodine monochloride, iodine monobromide, etc.), their pyridine adducts (PyICl, etc.), N-iodoimides, metal iodides, and the like. In particular, iodine and iodine monochloride are preferred. Further, in order to increase the reaction rate, Lewis acids such as aluminum chloride, zinc chloride, titanium tetrachloride, boron trifluoride, etc. may be added or light irradiation may be performed. The electrophilic reagent may be added in an amount of 1 mol or more, up to about 2 mol, per mol of the trialkylsilyl group to be iodinated. In order to avoid inducing side reactions, it is more preferable to adjust the amount added while monitoring the reaction as described below. The iodine-containing electrophilic reagent can also be added after being dissolved in the following solvent.

Examples of the solvent used in the reaction include acetic acid, methylene chloride, chloroform, carbon tetrachloride, and chlorobenzene, with halogenated hydrocarbons being particularly preferred. The reaction temperature is preferably 0° C. or higher and lower than the boiling point of the solvent, particularly preferably 10° C. or higher and 40° C. or lower for economic reasons. The reaction may be carried out under conditions of refluxing the solvent.
The atmosphere in which the reaction is carried out is not particularly limited, but the reaction can be carried out in an inert gas atmosphere such as nitrogen. By preventing moisture from entering the reaction system in such an atmosphere, it is possible to avoid hydrolysis of raw materials and products during the reaction.

From the viewpoint of yield, it is desirable to monitor the reaction rate by gas chromatography (GC) or the like and complete the reaction, but the reaction time may be about 0.1 to 5 hours from the end of dropping the electrophilic reagent.

Depending on the iodine-containing electrophile (IX), trialkylhalosilanes can be obtained as by-products (when the counter substituent X of iodine is a halogen). In this case, after the reaction is completed, the desired product can be obtained by distilling off the trialkylhalosilanes obtained as by-products together with the reaction solvent under reduced pressure. As a further alternative, a mixture of alcohol and amine may be added as a reaction terminator once the reaction raw materials have disappeared. Thereby, it is possible to suppress side reactions that proceed during post-treatment of the reaction. Upon addition of the alcohol and amine mixture, the trialkylhalosilane reacts to form the amine salt of the trialkylalkoxysilane and hydrogen halide. After filtering off the formed amine salt, the alcohol, amine and reaction solvent can be distilled off to obtain an iodine-containing silicon compound. It is preferable to use iodine monochloride as the iodine-containing electrophilic reagent because the by-produced trialkylchlorosilane can be easily separated from the product as described above.

The iodized phenyl group-containing silicon compound that can be produced by the method of the present invention as described above is not particularly limited, but the following compounds can be exemplified.

The obtained iodine-containing silicon compound can be used as it is for producing iodine-containing polysiloxane, or in some cases, after being purified by distillation, it can be used for producing iodine-containing polysiloxane.

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples and Comparative Examples, but the present invention is not limited to the Examples below.

[Example 1]
A reflux condenser and a thermometer were attached to a 300 ml three-necked glass flask, and the inside was purged with nitrogen. This flask was charged with 27 g (0.1 mol) of 4-trimethylsilylphenyltrimethoxysilane and 80 g of methylene chloride. While stirring with a magnetic stirrer, the internal temperature was adjusted to 10° C., and a mixture of 16.5 g of iodine monochloride and 80 g of methylene chloride was added dropwise over 30 minutes, followed by aging at 25° C. for 1 hour. When the reaction was confirmed by GC, it was found that the raw materials had disappeared, so the reaction solution was concentrated using a rotary evaporator to obtain crude 4-iodinated phenyltrimethoxysilane. This was distilled under reduced pressure to obtain 28.9 g (0.09 mol) of 4-iodinated phenyltrimethoxysilane. The yield was 89%.

[Example 2]
A reflux condenser and a thermometer were attached to a 500 ml three-necked glass flask, and the inside was purged with nitrogen. This flask was charged with 34 g (0.1 mol) of 3-trimethylsilylphenylethyltriethoxysilane and 100 g of methylene chloride. While stirring with a magnetic stirrer, the internal temperature was adjusted to 10° C., and a mixture of 16.5 g of iodine monochloride and 80 g of methylene chloride was added dropwise over 30 minutes, followed by aging at 25° C. for 1 hour. When the reaction was confirmed by GC, the raw materials had disappeared, so a mixture of 15 g of triethylamine and 20 g of ethanol was added dropwise at 25°C over 5 minutes, and the mixture was aged at 25°C for 30 minutes. 100 g of hexane was added to the reaction solution to precipitate triethylamine hydrochloride, which was filtered off and the filtrate was concentrated using a rotary evaporator to obtain crude 3-iodinated phenylethyltriethoxysilane. This was distilled under reduced pressure to obtain 36.1 g (0.09 mol) of 3-iodinated phenylethyltriethoxysilane. The yield was 92%.

[Example 3]
A reflux condenser and a thermometer were attached to a 1000 ml three-necked glass flask, and the inside was purged with nitrogen. This flask was charged with 34 g (0.1 mol) of 3,4-bistrimethylsilylphenyltrimethoxysilane and 200 g of methylene chloride. The internal temperature was adjusted to 10° C. while stirring with a magnetic stirrer, and a mixture of 33 g of iodine monochloride and 200 g of methylene chloride was added dropwise over 30 minutes, followed by aging at 25° C. for 2 hours. When the reaction was confirmed by GC, the raw materials had disappeared, so a mixture of 30 g of triethylamine and 30 g of methanol was added dropwise at 25°C over 10 minutes, and the mixture was aged at 25°C for 30 minutes. 300 g of hexane was added to the reaction solution to precipitate triethylamine hydrochloride, which was filtered off and the filtrate was concentrated using a rotary evaporator to obtain crude 3,4-diiodide phenyltrimethoxysilane. This was distilled under reduced pressure to obtain 38.4 g (0.09 mol) of 3,4-diiodinated phenyltrimethoxysilane. The yield was 84%.

[Comparative synthesis example 1]
A reflux condenser and a thermometer were attached to a 300 ml three-necked glass flask, and the inside was purged with nitrogen. This flask was charged with 20 g (0.1 mol) of phenyltrimethoxysilane and 80 g of methylene chloride. While stirring with a magnetic stirrer, the internal temperature was adjusted to 10°C, and a mixture of 16.5 g of iodine monochloride and 80 g of methylene chloride was added dropwise over 30 minutes, followed by aging at 25°C for 1 hour. The reaction was confirmed by GC, but raw materials remained unreacted. When the reaction temperature was further increased to 40° C. and the reaction was continued for 3 hours, the raw materials were decomposed and a peak of iodized benzene was generated.

[Comparative synthesis example 2]
A reflux condenser and a thermometer were attached to a 300 ml three-necked glass flask, and the inside was purged with nitrogen. This flask was charged with 23 g (0.1 mol) of phenylethyltrimethoxysilane and 80 g of methylene chloride. While stirring with a magnetic stirrer, the internal temperature was adjusted to 10°C, and a mixture of 16.5 g of iodine monochloride and 80 g of methylene chloride was added dropwise over 30 minutes, followed by aging at 25°C for 1 hour. The reaction was confirmed by GC, but raw materials remained unreacted. Further, the reaction temperature was raised to 40° C. and the reaction was continued for 30 hours, but no progress of the reaction was observed.

In the examples, by reacting at 25°C (about room temperature) for 1 to 2 hours, the raw materials can be eliminated without decomposition, and the desired iodized phenyl group-containing silicon compound can be obtained in high yield. can be obtained.
On the other hand, in the comparative example, since a raw material different from the trialkylsilylphenyl group-containing silicon compound used in the present invention is used, even if iodine monochloride is used as the iodine-containing electrophile, the raw material does not disappear at around room temperature. If the reaction temperature is increased and the reaction time is also increased, the raw materials will decompose, making it impossible to obtain the desired iodized phenyl group-containing silicon compound.

The above results show that it is possible to produce iodine-containing silicon compounds by replacing trialkylsilyl groups with iodine under mild conditions in a short time. It has been shown that phenyl group-containing silicon compounds can be produced economically.
In the present invention, it is possible to economically produce a hydrolyzable silicon compound containing an iodide phenyl group for forming a polysiloxane underlayer film containing an iodide phenyl group, which is expected to improve the performance of EUV lithography. Very expensive.

Note that the present invention is not limited to the above embodiments. The above-mentioned embodiments are illustrative, and any embodiment that has substantially the same configuration as the technical idea stated in the claims of the present invention and has similar effects is the present invention. covered within the technical scope of.

Claims (3)

An iodized phenyl group-containing compound represented by the following reaction formula, characterized in that the trialkylsilyl ((R ⁰ ) ₃ Si) group bonded to the phenyl group is replaced with iodine by an iodine-containing electrophile (IX) Method for producing silicon compounds.

(In the above reaction formula, R ⁰ is an alkyl group having 1 to 6 carbon atoms, which may be the same or different, R ¹ is a single bond or a divalent organic group, and the divalent organic group is A linear, branched or cyclic alkylene group, carbonyl group, ^ester group (carbonyloxy group), ether group, or a combination thereof; 10 branched or cyclic alkyl groups , where the alkyl group may further have an ester group or an ether group, and R ³ is a linear chain having 1 to 10 carbon atoms or a straight chain having 3 carbon atoms. ~10 branched or cyclic alkyl groups or alkoxy groups , where the alkyl group may further have an ester group or ether group, and R is a linear or alkoxy group having 1 to 6 carbon atoms. is a branched or cyclic alkyl group having 3 to 6 carbon atoms. n0 is 1, 2 or 3, n1 is 1, 2 or 3, n2 is 0, 1 or 2, n3 is 0, 1 or 2, 1 ≦n1+n3≦3, and X is the opposite substituent of iodine that acts as an electrophilic active species.) The method for producing an iodized phenyl group-containing silicon compound according to claim 1, wherein the R ⁰ is a methyl group or an ethyl group. The method for producing an iodized phenyl group-containing silicon compound according to claim 1 or 2, wherein the iodine-containing electrophile is iodine monochloride.